1. Field of the Invention
The present invention relates to a technique for supplying ink for an image forming apparatus, such as a liquid printer, which can uniformly supply ink across the entire width of a developing roller.
2. Description of the Related Art
In an image forming apparatus such as a liquid printer, includes a developing unit for developing an image on an electrostatic image area formed on a surface of a photoreceptor web using ink and an ink supplying apparatus for supplying ink to the developing unit.
The ink supplying apparatus includes an ink container containing ink of a predetermined color, a supply pump for pumping the ink into the ink container, a manifold through which the ink pumped by the supply pump is injected to a development gap formed between the developing roller and the photoreceptor web, and an ink supply pipe connected between the lower portion of the middle of the manifold and the supply pump.
In such an ink supplying apparatus, since the inner diameter of the ink supply pipe is smaller than an inner space of the manifold, a change in pressure is generated between the ink and the ink supply pipe and the ink supplied into the manifold. Such a difference in pressure causes the ink to be supplied mainly to the middle portion of the developing roller. Therefore, the concentration of ink on an image developed in the electrostatic latent image area by the developing roller becomes irregular, thus lowering the quality of the image.